Simpler notify syntax

No need for list when there's just 1 handler

tasks/main.yml

@@ -36,28 +36,24 @@
 - name: install elasticsearch
   package:
     name: elasticsearch-oss
-  notify:
-    - restart elasticsearch
+  notify: restart elasticsearch
 
 - name: configure elasticsearch
   copy:
     src: elasticsearch.yml
     dest: /etc/elasticsearch/elasticsearch.yml
-  notify:
-    - restart elasticsearch
+  notify: restart elasticsearch
 
 - name: install nginx
   package:
     name: nginx
-  notify:
-    - restart nginx
+  notify: restart nginx
 
 - name: configure nginx
   copy:
     src: nginx.conf
     dest: /etc/nginx/sites-available/default
-  notify:
-    - restart nginx
+  notify: restart nginx
 
 - name: graylog apt repo
   apt:
@@ -67,8 +63,7 @@
   apt:
     update_cache: True
     name: graylog-server
-  notify:
-    - restart graylog
+  notify: restart graylog
 
 - name: configure graylog
   template: